1. Technical Field
The present invention relates to a display apparatus, and, more particularly, to a liquid crystal display.
2. Discussion of the Related Art
A liquid crystal display is one of the most widely used flat panel displays. Liquid crystal displays include two panels provided with field-generating electrodes such as pixel electrodes and a common electrode and a liquid crystal layer interposed therebetween. The liquid crystal display displays images by applying voltages to the field-generating electrodes to generate an electric field in the liquid crystal layer, which determines orientations of liquid crystal molecules in the liquid crystal layer to adjust polarization of incident light.
A vertical alignment mode liquid crystal display, in which liquid crystal molecules are aligned such that the long axes of the liquid crystal molecules are perpendicular to the two panels (i.e., upper and lower panels) in the absence of an electric field, has become the focus of attention because of its high contrast ratio and wide reference viewing angle, which is defined as a viewing angle making the contrast ratio equal to 1:10 or as a limit angle for the inversion in luminance (brightness) between the grays.
In the vertical alignment mode liquid crystal display, the wide viewing angle can be achieved by forming cutouts in field-generating electrodes and forming protrusions on the field-generating electrodes. Since the cutouts and the protrusions can determine the tilt directions of the liquid crystal LC molecules, the tilt directions can be distributed into several directions by using the cutouts and the protrusions such that the reference viewing angle is widened.
The conventional vertical alignment mode liquid crystal display has relatively poor lateral visibility compared with front visibility. For example, a patterned VA (PVA) mode LCD having the cutouts shows an image that becomes bright as it goes far from the front, and, in the worst case, the luminance difference between high grays vanishes such that the images cannot be perceived.